Re: [PATCH] Btrfs: do not mount when we have a sectorsize larger than PAGE_SIZE

[Liu Bo <liubo2009@cn.fujitsu.com>]

On 04/02/2012 08:17 PM, David Sterba wrote:
> On Mon, Apr 02, 2012 at 07:28:18PM +0800, Liu Bo wrote:
>> --- a/fs/btrfs/disk-io.c
>> +++ b/fs/btrfs/disk-io.c
>> @@ -2104,6 +2104,14 @@ int open_ctree(struct super_block *sb,
>>  		err = -EINVAL;
>>  		goto fail_alloc;
>>  	}
>> +	if (btrfs_super_sectorsize(disk_super) > PAGE_CACHE_SIZE) {
>> +		printk(KERN_ERR "BTRFS: couldn't mount because sectorsize(%d)"
>> +		       " was larger than PAGE_SIZE(%lu)\n",
> 
> %llu
> 

err, thanks for caching it.

>> +		       btrfs_super_sectorsize(disk_super),
>> +		       (unsigned long long)PAGE_CACHE_SIZE);
>> +		err = -EINVAL;
>> +		goto fail_alloc;
>> +	}
>>  
>>  	features = btrfs_super_incompat_flags(disk_super);
>>  	features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
> 
> We have the opposite check a few lines below
> 
> 2257         if (sectorsize < PAGE_SIZE) {
> 2258                 printk(KERN_WARNING "btrfs: Incompatible sector size "
> 2259                        "found on %s\n", sb->s_id);
> 2260                 goto fail_sb_buffer;
> 2261         }
> 2262
> 
> so sectorsize must be equal to PAGE_SIZE always and one check can catch
> both cases.
> 

But this check is _useless_ when we have a sectorsize which is larger than PAGE_SIZE,
we're not ready for that, too.

We already have one check, so I'll modify this instead. :)

thanks,
liubo

> 
> david
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